DE102014111241A1 - Sheet metal or sintered part for a stator or a rotor of an electrical machine and method for its production - Google Patents

Abstract

The invention relates to a sheet metal or sintered part (10) for a stator or a rotor of an electrical machine, for example an electric motor, and to a method for producing such a sheet metal or sintered part (10). The sheet metal or sintered part 10 has a connecting part (11), from which regularly spaced teeth (12) protrude. At the free end, each tooth (12) has a tooth head (14) which is connected to the connecting part (11) via a toothed web (13). Each tooth has at least a first toothed segment (22) and at least one second toothed segment (23). The tooth segments are made of different magnetizable materials (M1, M2). In this way, the materials (M1, M2) can be used specifically with regard to their magnetic and / or mechanical properties in the region of the tooth (12), where they can influence the magnetic and / or mechanical behavior of the tooth (12) and thus of the sheet metal. or sintered parts (10) can optimize. In particular, at least one first toothed segment (22) is present on the tooth head (14) whose saturation magnetization BS1 is greater than that of the remaining sheet metal or sintered part (10).

Description

The invention relates to a sheet metal or sintered part for a stator or stator or a rotor or rotor of an electrical machine, for example an electric motor. This sheet metal or sintered part can also be referred to as Läufererblech or stator. The invention also relates to a method for producing such a sheet metal or sintered part. The rotor can rotate about a rotation axis (rotor) or, in the case of a translationally operating electric machine, move linearly along the stator or stator.

It is known to combine laminated cores of a plurality of sheet metal or sintered parts by stamped packetizing, gluing or the like. Such a laminated core is then part of a rotor or rotor or a stator of an electric motor.

Each sheet or sintered part has a connecting part, from which several teeth extend away. For a rotary electric machine, the connecting part is closed in a circumferential direction about an axis of rotation designed as a ring part. The teeth extend from the connecting part radially to the axis of rotation either outwardly or inwardly. In an electric machine, in which the rotor translates on a movement path along the stator, the connecting part preferably extends in a straight line or curved and the teeth preferably protrude at right angles to the direction of movement of the rotor away from the connecting part and are in particular aligned parallel to each other.

At the free end of each tooth, a tooth head is present, which is connected via a toothed bridge with the connecting part. The tooth head has a tooth head surface, from which the magnetic field lines emerge from the sheet metal or sintered part.

Many attempts have been made to improve the efficiency of electrical machines by optimizing the sheet or sintered parts or the sheet metal packages produced from the sheet metal or sintered parts.

For example, beats DE 10 2012 213 239 A1 To use two different types of sheet metal or sintered parts and to stack these sheet metal parts in the laminated core alternately to each other. The different sheet metal parts are made of different materials. One sheet metal part may consist of a nickel-iron alloy and the other sheet metal part of an iron-cobalt alloy. As a result, sheet metal parts with a low loss coefficient on the one hand and high saturation flux density on the other hand are to be combined to form a laminated core.

In DE 10 2010 049 178 A1 an electric machine is proposed, which should enable operation in a wide speed range. In particular, the proportions of the stator current should be reduced at high speeds. For this purpose, the rotor should have a means for setting a magnetic field strength or a flux density of the stator portion of the exciting field generated by the rotor. For this purpose, the magnetic resistance within the rotor can be changed by a recess or an insertion element inserted into the recess.

It is also known to optimize the efficiency of an electrical machine by the contour or geometry of the sheet metal parts which form the laminated core of the stator or of the rotor. However, it has been shown that these optimization attempts reach their limits.

Based on the prior art, the present invention seeks to provide a sheet or sintered part, with which an improved electric machine can be produced.

The object is achieved by the provision of a sheet metal or sintered part for a stator or a rotor of an electrical machine with the features of claim 1. An inventive method for producing such a sheet or sintered part is specified in claim 16.

The sheet or sintered part is used to create a package or laminated core of a stator or a rotor. An electric machine can thus have in the rotor and / or in the stator a package or laminated core of a plurality of sheet metal or sintered parts according to the invention. The sheet-metal or sintered part has, for a rotary electric machine, a connecting part which is annularly closed in a circumferential direction about a rotation axis. From the connecting part several teeth protrude. The teeth are distributed in the circumferential direction about the axis of rotation at equal intervals.

The sheet metal or sintered part has, for a translationally operating electric machine (for example a linear drive), a connecting part extending in a straight line or curved along the path of movement of a rotor, from which the teeth extend at preferably equally spaced intervals.

The teeth have a toothed ridge which is connected to the connecting part. At the connection part opposite the free end Each tooth has a tooth tip. In the installation position during operation of the electric machine, magnetic field lines emerge from the tooth tip, in particular at a tooth head surface, whose one extension component runs in the circumferential direction about the rotation axis and whose other extension component runs along the rotation axis (rotationally operating machine). The tooth head surface points at a sheet or sintered part for a translational machine away from the connecting part and has an extension component in the direction of movement of the rotor and another extension component at right angles thereto.

According to the invention, each tooth consists of at least two different magnetizable materials. Each tooth has at least one first toothed segment of a magnetizable first material and at least one second toothed segment of a magnetizable second material. The two magnetizable materials differ from each other. As a result, it is possible to produce those parts of a tooth in which a magnetic field having a high magnetic flux density is formed, at least temporarily, during operation of the electrical machine, from a material having a correspondingly large saturation magnetization. Such materials with a large saturation magnetization are usually expensive. In addition, in some cases they do not have sufficient magnetic permeability or sufficient mechanical stability. In turn, other magnetizable materials are mechanically stable enough and / or have high magnetic permeability but again have low saturation magnetization. The inventive design of the teeth, each with at least one first toothed segment and at least one second toothed segment made of different materials, the materials can be targeted in terms of their magnetic and / or mechanical and / or physical properties in the spatial segment of the tooth used to total in terms to obtain an improved sheet or sintered part on the magnetic and / or physical and / or mechanical properties.

As the first material, for example, an iron alloy having a content of at least 45% or at least 50% cobalt can be used. Iron alloys containing nickel and / or molybdenum can also be used.

As the second material for the second sector gear, so-called "mu-metals" or iron alloys having nickel components and / or silicon components are preferably used.

The connecting part of the sheet metal or sintered part may be made of the same material as the second toothed segment.

Both the first material and the second material are preferably a soft magnetic material. In particular, the entire sheet or sintered part is made of two or more soft magnetic materials.

Preferably, the first material has a greater saturation magnetization than the second material. The saturation magnetization of the first material may be, for example, at least 2.0 T or 2.3 T or 2.5 T or 3.0 T. The saturation magnetization of the second material is preferably at most 1.0 t.

In a preferred embodiment, the relative permeability of the first material is less than that of the second material. For example, the first material has a relative permeability of at most 20,000. The relative permeability of the second material may be at least 30,000 and, in one embodiment, in the range of 100,000 to 200,000.

Preferably, the volume fraction of the first material of a tooth is smaller than the volume fraction of the second material of the same tooth.

In one embodiment, the first toothed segment forms at least a part of the tooth head. In one embodiment, the entire tooth tip may be formed by the first toothed segment. In another embodiment, the tooth tip may include a toothed segment having at least a portion of the tooth tip surface from which the magnetic field lines emerge during operation of the electrical machine.

Viewed in the circumferential direction about the axis of rotation or viewed in the direction of movement of the rotor, the tooth head may have two opposite end portions. At least one of these two end portions may be formed by a first toothed segment and thus consist of a first material. In the area of these end sections, when the rotor rotates relative to the stator, a magnetic flux density which is large in magnitude can be formed. It is therefore advantageous to provide in at least one of these end portions a first toothed segment, which consists of a material having a large saturation magnetization.

If the electric machine is to have a high drive or torque in both directions of movement or rotation, it is advantageous to form both end sections of the tooth head by a first toothed segment in each case. at For electric machines operated with a large torque only or mainly in a driving direction, it may be sufficient to form only one end portion of the tooth tip through a first tooth segment.

It is possible to make the tooth asymmetric with respect to the materials used to a longitudinal center plane or symmetrically to the longitudinal center plane. The longitudinal center plane is formed by a radial plane which extends centrally through the tooth or tooth bridge. If, for example, only a single first toothed segment is present, then the tooth can be asymmetrical to the longitudinal center plane in that this first toothed segment is not arranged symmetrically with respect to the longitudinal center plane.

If two or more first tooth segments are present, the tooth may be symmetrical or asymmetrical to the longitudinal center plane. An asymmetrical embodiment with two first toothed segments is achieved, for example, if the two first toothed segments arranged on opposite sides of the longitudinal center plane have a different shape and / or size.

Preferably, the second toothed segment forms at least a part of the toothed web. In particular, at least a portion between the connecting part and the tooth tip of the toothed bar is formed by the second toothed segment.

It is advantageous if the connecting part and the second toothed segment and / or the toothed web consist of the same material. This makes it possible to produce the tooth webs of the teeth and the connecting part during manufacture of the sheet or sintered part at the same time, for example, by separating it from an output sheet. It is also possible that a central portion of the tooth head viewed in the circumferential direction about the axis of rotation or in the direction of movement of the rotor consists of the same material as the toothed bar and / or the connecting part.

In one embodiment, it is also possible that the connecting part consists of a magnetizable third material, which differs from the first and the second material. As a result, the sheet metal or sintered part can be further optimized with regard to its magnetic and / or mechanical and / or physical properties.

It is advantageous if the second material and / or the third material has a higher mechanical stability than the first material. The mechanical stability is to be understood as meaning the tensile strength and / or the elastic modulus and / or the hardness.

In a preferred embodiment, a tooth tip passing through the tooth tip surface may be present in a tooth tip. Such a groove serves to reduce the radial forces during operation of the electric machine.

The at least one first toothed segment and the at least one second toothed segment are positively and / or materially and / or non-positively connected to the respectively adjacent part of the sheet metal or sintered part. The cohesive connection can be produced for example by gluing, welding, stamping or laser welding. Additionally or alternatively, undercut contours may be formed in the regions to be connected in order to produce a positive engagement.

For the production of the sheet metal or sintered part can proceed as follows:

First, the at least one first toothed segment and the at least one second toothed segment are produced. For example, the tooth segments can be cut out of a respective starting sheet, by cutting, stamping, laser cutting, water jet cutting or the like. Subsequently, the toothed segments produced are bonded together in a material-locking and / or positive-locking and / or non-positive manner.

The second tooth segments of the teeth can be made integral, without seam and joint together with the connecting part, for example, be cut out simultaneously with the connecting part of an output sheet. If the connecting part and the second tooth segments of the sheet metal or sintered part are made of different materials, the second toothed segments are connected to the connecting part before or after the connection to the respective at least one associated first toothed segment.

Additionally or alternatively, it is also possible to separate out the first and / or second toothed segments from an output sheet by punching according to a stamping method, in which the output sheet is clamped over a sheet holding device. The clamping force of the sheet holding device may be varied depending on the position of a punch carrying the punch to improve the quality of the punching edges. Such a method is in EP 1 602 419 A1 described. With respect to the punching of the sheet metal or sintered part or the tooth segments or the connecting part from a respective output sheet is on the in EP 1 602 419 A1 described method at this point expressly incorporated.

Advantageous embodiments of the invention will become apparent from the dependent claims, as well as the description and the drawings. Hereinafter, preferred embodiments will be explained with reference to the accompanying drawings in detail. Show it:

1 a schematic partial view of a sheet or sintered part for a rotor in side view,

2 a schematic partial view of a sheet metal or sintered part for a stator in side view,

3 to 6 in each case an embodiment of a tooth with a plurality of tooth segments, the component of a sheet metal or sintered part according to 1 or 2 is and

7 a schematic diagram of a portion of the magnetic field between a tooth of a rotor and a tooth of a stator.

In 1 is a sheet metal part in a schematic partial representation 10 for a rotor of an electric motor illustrated. Made of several such sheet metal parts 10 a laminated core is created for the rotor. The sheet metal parts 10 are connected, for example, by gluing, stamping packages or other means to a laminated core.

In 2 is schematically another embodiment of a sheet metal part 10 illustrated used in a stator of an electric motor. Like the rotor, the stator also has several such sheet metal parts 10 layered or stacked and connected to a laminated core.

Instead of sheet metal parts used here in connection with the drawing example 10 Alternatively, sintered parts made of a sintered material could be used.

The sheet metal parts 10 according to the 1 and 2 have a form for building an external rotor motor. The rotor encloses the radially further inwardly arranged stator. It is understood that other embodiments with a radially outer stator and a radially inner rotor (inner rotor motor) are executable.

The sheet metal part 10 has a in a circumferential direction U about a rotational axis D annularly closed connection part 11 , From the connecting part 11 several teeth protrude 12 path. The number of teeth 12 varies and depends on the design of the stator or rotor. Also the sizing of the teeth 12 and their contour may vary. The teeth 12 extend radially to the axis of rotation D. The teeth 12 of the sheet metal part 10 can be like in 1 illustrated starting from the connecting part 11 radially inward or as in 2 represented starting from the connecting part 11 extend radially outward. In the 1 and 2 is seen in the circumferential direction U only a part of the sheet metal part 10 illustrated. The sheet metal parts 10 are completely closed in the circumferential direction U, the teeth 12 are each distributed at a uniform distance in the circumferential direction U.

This annular design of a sheet or sintered part 10 is intended for rotary electric machines. In a modification to the illustrated embodiments, the connecting part 11 Also straight or curved along a trajectory of a rotor of a translationally operating electric machine (linear drive or linear generator) extend. The teeth 12 thereby protrude at right angles to the movement path or direction of movement of the runner from the connecting part 11 path. Incidentally, the sheet or sintered part 10 for the stator or rotor of a translationally working electrical machine corresponding to the sheet metal or sintered parts 10 be constructed, which are explained in connection with the drawing. The circumferential direction about the axis of rotation is to be replaced by the linear direction of movement of the rotor.

In the 3 to 7 is in each case a section of a sheet metal part 10 with several teeth 12 shown enlarged. Based on these figures, the structure of the teeth 12 explained. All teeth 12 a sheet metal part 10 are constructed identically so that it is sufficient to build a single tooth 12 to explain.

Every tooth 12 has a tooth bridge 13 that with the connecting part 11 connected is. The tooth bridge 13 extends from the connection part 11 radial to the axis of rotation D. At the of the connecting part 11 opposite end of the toothed bridge 13 shows the tooth 12 a tooth head 14 on. In the circumferential direction U of the tooth head 14 on both sides over the tooth bridge 13 stick out and the tooth 12 in its extension direction to its free end 15 expand. The tooth shape or tooth contour may be opposite to a longitudinal center plane L of the tooth 12 be symmetric or unbalanced. In the embodiments illustrated here, the tooth shape, ie the outer contour of the tooth 12 executed symmetrically to the longitudinal center plane L. The longitudinal center plane L extends centrally through the toothed web 13 and forms a radial plane with respect to the axis of rotation D.

At his free end 15 shows the tooth 12 a tooth head surface 16 on. The tooth head surface 16 has an extension component in the circumferential direction U and an extension component parallel to the rotation axis D. Preferably, the Zahnkopfflächen run 16 the teeth 12 along a common cylinder jacket surface about the axis of rotation D, which is schematically in the 1 and 2 is illustrated.

In one embodiment, the tooth head surface 16 through a groove 17 ( 3 ) be divided into two separate surface sections. The groove 17 extends parallel to the axis of rotation D in the region of the free end 15 through the tooth head 14 , The groove 17 is optional and can be used in all described embodiments of the sheet metal part 10 in the teeth 12 to be available.

Each tooth has at least a first toothed segment 22 and at least one second sector gear 23 , The first toothed segment 22 consists of a magnetizable first material M1. The second toothed segment 23 consists of a magnetizable second material M2. In the exemplary embodiment, the first material M1 and the second material M2 are each a soft-magnetic material. The two materials M1, M2 differ from each other.

As in the 3 to 7 illustrated is in the area between two adjacent teeth 12 or between two adjacent tooth webs 13 a winding 18 the stator or the rotor of an electrical machine available. The winding 18 is illustrated in a highly schematic manner. Instead of such a winding 18 can also be permanent magnets on a stator or a rotor 19 between adjacent teeth 12 be arranged ( 7 ).

In the preferred exemplary embodiments described here, this forms at least one first toothed segment 22 at least a part of the tooth head 14 a tooth 12 , According to the first embodiment 3 is the tooth head 12 in total by a first toothed segment 22 educated. The tooth bridge 13 is here through the second sector gear 23 educated. The first toothed segment 22 and therefore the tooth head 14 is at a first junction 25 with the tooth bridge 13 or the second toothed segment 23 connected. The second toothed segment 23 is at a second connection point 26 with the connecting part 12 connected.

According to the example, the first material M1 of the first toothed segment has 22 a first saturation magnetization B _S1 and the second material a second saturation magnetization B _S2 . The first saturation magnetization B _S1 is greater than the second saturation magnetization B _S2 . The first saturation magnetization B _S1 is preferably at least 2.0 T or 2.3 T or 2.5 T. The second saturation magnetization B _S2 is preferably at most 1.0 T.

The first material has a first relative permeability μ _r1 that is less than the second relative permeability μ _{r2 of the} second material M2. The second relative permeability μ _r2 is preferably greater than 30,000 or greater than 100,000 and may be in the range of 100,000 to 200,000. The first relative permeability μ _r1 is preferably less than 20,000.

The first material M1 may be an iron alloy containing at least 45% or at least 50% cobalt. Alloy having a nickel content or molybdenum content or combinations thereof may also be used. As a second material, a so-called Mu metal is preferably used. The second material may be an iron alloy having a nickel component or a silicon component.

The materials that can be used as second material M2 can also be used for the connecting part 11 be used, with no material identity between the connecting part 11 and the second toothed segment 23 must exist, although the use of identical materials for the connecting part 11 and the second toothed segment 23 in a sheet metal part 10 is possible and to simplify the manufacture of the structure of the sheet metal part 10 may be advantageous.

Characterized in that the at least one first toothed segment 22 at least a part of the tooth head 14 and the at least one second toothed segment 23 at least part of the tooth bridge 13 forms, can for the two tooth segments 22 . 23 the respectively optimal materials M1 and M2 are used with regard to the magnetic and / or mechanical and / or physical properties. The tooth 12 or the sheet metal part 10 can thus be optimized and the material costs kept low. Often, materials with high saturation magnetization are very expensive. By using such a material only for at least a first toothed segment 22 in the area of the tooth head 14 can reduce the material costs for a sheet metal part 10 and a rotor or a stator of a plurality of such sheet metal parts 10 be kept low. Such materials are used only where there are the magnetic properties of the tooth 12 require, for example, in the region of the tooth head 14 , Other sections of the tooth 12 are optimized through the use of other materials.

At the in 4 illustrated embodiment is in contrast to the first embodiment according to 3 only a part of the respective tooth head 14 by at least a first toothed segment 22 educated. According to the example, the tooth head 14 a tooth 12 two end portions arranged in the circumferential direction U at opposite ends 24 on. The two end sections 24 are arranged in the circumferential direction U at a distance from each other and touch, for example, not. In a modification to the preferred embodiments described herein, the two end portions could 24 at the tooth head surface 16 also connect directly to each other.

In the embodiment according to 4 shows the tooth 12 , as in the first embodiment according to 3 , a second toothed segment 23 from the second material M2. In contrast to the first embodiment according to 3 the second toothed segment extends 23 according to the embodiment 4 in the region of the longitudinal median plane L in the tooth tip 14 into it. The second toothed segment 23 forms according to the example in the region of the longitudinal center plane a central portion of the tooth head surface 16 ,

In the circumferential direction U, the tooth head 14 two end sections 24 on, each by a first toothed segment 22 are formed. Each of the two tooth segments 22 or each end section 24 represents a section of the tooth head surface 16 ready, which adjoins the middle section passing through the second sector gear 23 is provided. The first two segments 22 are thus at each of a first connection point 25 with the second toothed segment 23 of the tooth 12 connected. The second toothed segment 23 is at the second junction 26 , as in the first embodiment according to 3 , with the connecting part 12 connected. In contrast to the second embodiment according to 4 is in the first embodiment after 3 only a first connection point 25 present, as the tooth head 14 in total by a single first toothed segment 22 is formed.

The connection at a first connection point 25 and / or at a second connection point 26 is in the embodiments according to the 3 and 4 cohesively executed. The cohesive connection can be produced by welding, laser welding, gluing, sintering or another suitable cohesive connection. The cohesive connection at a connection point 25 . 26 can be over the entire surface or at partial, for example, point or line, done.

In the 3 and 4 are at the connection points 25 . 26 each flat connecting surfaces provided, which through the rectilinear connection points 25 . 26 is shown. It is understood that in a modification to this also curved and / or jagged or any other gradients of the first joint 25 and / or the second connection point 26 possible are. In particular, wave-shaped, jagged or other non-linear courses of a connection point 25 . 26 the interface at a respective junction 25 . 26 be enlarged. In addition to mechanical improvements of the connection, this can also influence the magnetic resistance. The course of the connection points 25 . 26 also has an effect on the forces in the magnetic field occurring at this interface due to the changing relative permeability, which act perpendicular to the interface on the material with lower relative permeability.

In 5 is schematically illustrated another way how the connection between the tooth segments 22 . 23 with each other or to other parts of the sheet metal part 10 or with the connecting part 11 can be realized. Alternatively, but preferably in addition to the cohesive connection, a positive connection at the first connection point 25 and / or the second connection point 26 be provided. For this are the contours of the parts of the tooth to be joined 12 adapted to each other so that projections and undercut recesses fit into each other, so that a positive connection is formed, similar to interlocking puzzle pieces or a dovetail joint. The positive connection of the parts of the tooth 12 can be done by juxtaposing parallel to the axis of rotation D. A pulling apart of the parts thus connected transversely to the connector direction (parallel to the axis of rotation D) is prevented. The in the 5 and 6 illustrated contours that at the connecting part 11 and on the second toothed segment 23 as well as on the respective first toothed segment 22 Form projections and / or recesses are merely exemplary. In this case, any other courses of the first and / or second connection point are possible.

In the production of the positive connection may additionally or alternatively to a cohesive connection and a non-positive connection at a first connection point 25 and / or a second connection point 26 getting produced.

In the embodiments according to the 3 to 5 and 7 is every tooth 12 designed symmetrically to its longitudinal center plane L. In contrast, it is also possible to get the tooth 12 with respect to the longitudinal center plane L with respect to the materials used asymmetric perform. For example, the tooth 12 only on one side of the longitudinal center plane L at one of the two end portions 24 through a first toothed segment 22 consist of the first material M1, while the respect to the longitudinal center plane L opposite end portion is made of a different material. In this asymmetrical design, the outer contour of the tooth 12 still be symmetrical to the longitudinal center plane L, while the arrangement of the various tooth segments 22 . 23 for the formation of the tooth 12 have no symmetry with respect to the longitudinal center plane L.

According to the embodiment 6 is thus only an end section 24 of the tooth head 14 through a first toothed segment 22 and thus made of the first material M1. By way of example, the first material M1 has a first saturation magnetization B _S1 which is greater than the second saturation magnetization B _{S2 of} the second material M2. Such a design may be the cost of producing a sheet metal part 10 reduce further and is particularly suitable for electrical machines that are moved only or mainly in a rotational direction about the rotation axis D. For example, electric motors of vehicles such as cars, motorcycles or bicycles are driven almost exclusively in one direction of rotation. Even generators of power generation plants, such as hydroelectric power plants, wind turbines are operated only in one direction. This can be due to the asymmetrical design 6 Be taken into account.

In all embodiments, the total volume of the first material M1 of the at least one first toothed segment 22 smaller than the total volume of the second material M2 of the at least one second toothed segment 23 ,

As a modification to the illustrated embodiments, it is also possible that more than one second toothed segment 23 is available. Further, as a modification to the illustrated embodiments, the second connection point 26 between the tooth bridge 13 and the connecting part 11 omitted. It is possible the connecting part 11 and the tooth bridge 13 or the connecting part 11 and the at least one second toothed segment 23 integral without seam and joint made of the same material.

The in the embodiment according to 7 illustrated tooth 12 a rotor has a modified contour. The tooth head 14 does not project in the circumferential direction U over the toothed web 13 out. For example, this tooth tapers 12 to his free end 15 out.

Another aspect of the present invention relates to the tooth 12 one with permanent magnets 19 provided rotor or stator of an electrical machine, which is a flux guide 27 forms ( 7 ). Such flux conductors 27 can be used to calculate the magnetic flux density B in the permanent magnets 19 to limit. Conveniently, the Flussleitstücke protrude 27 in the radial direction with respect to the axis of rotation D via the adjacent permanent magnets 19 out and form opposite the associated teeth 12 of the associated stator or rotor, the air gap in which the magnetic field H is formed. This allows the permanent magnets 19 to be protected from excessive magnetic flux density and thus from demagnetization.

In 7 is highly schematic of the principal mode of action of the inventive design of the teeth 12 a sheet metal part 10 according to the embodiments of all present invention. Very much simplified at the top of the picture is a tooth 12 a rotor illustrates, here a Flussleitstück 27 between two permanent magnets 19 represents. The rotor could also be a sheet metal part 10 have one or more windings 18 having. It is assumed by way of example that the machine is an electric motor.

Some magnetic field lines of the magnetic field H are between the tooth 12 of the rotor and a tooth 12 of the stator illustrated. The direction of rotation R of the rotor about the axis of rotation D is illustrated schematically. The teeth 12 the sheet metal parts 10 of the rotor and the stator are carried out as described above.

When the rotor rotates in the direction of rotation R, the tooth approaches 12 of the rotor to a considered tooth 12 (middle tooth in 7 ) at. At this approach arises between the tooth 12 of the rotor and the considered tooth 12 of the stator the magnetic field H. In 7 is schematically illustrated the situation when the two considered teeth 12 Partially covered when viewed radially to the axis of rotation. In the two end sections 24 of the considered teeth 12 , which have the least distance from each other, creates a large magnetic flux density. If the magnetic flux density exceeds the saturation magnetization in the region of the respective end section 24 of the tooth head 14 , so by a further increase in current in the windings 18 the stator take place no further torque increase. A further increase in current would only lead to the generation of heat. That is why at least the one end section 24 every tooth 12 through a first toothed segment 22 formed having a large first saturation magnetization B _S1 . As a result, a high torque can be provided for an electric motor.

If, in a further rotation of the rotor in the direction of rotation R, the overlap of the two considered teeth 12 increases, the magnetic flux density B in the teeth decreases. Thus, it is not necessary to make the entire tooth from a first material M1 having a large first saturation magnetization B _S1 . It suffices those tooth segments and, for example, the first tooth segments 22 a tooth 12 made of the first material M1, which are subjected to a large magnetic flux density B during operation of the electric machine.

The connecting part 11 and / or the tooth bridge 13 or the second toothed segment 23 can be optimized for other magnetic and / or mechanical and / or physical properties than the saturation magnetization. In particular, the second toothed segment has 23 and thus, for example, the tooth bridge 13 and / or the connecting part 11 a high relative permeability, which is greater than that of the first material M1 or has a greater mechanical stability than the first material M1. The mechanical stability may be characterized by the tensile strength and / or the modulus of elasticity and / or the hardness of the material.

In all illustrated embodiments, the connecting part 11 are made of a magnetizable third material M3, which is different from the first material M1 and the second material M2. In particular, the third material M3 may have greater mechanical stability than the first material M1 and / or the second material M2. The third material M3 may also differ in magnetic and / or physical properties from the other two materials M1, M2.

In the production of the sheet metal part 10 the procedure is as follows:
From a first output sheet consisting of the first material M1, the first tooth segments 22 the teeth 12 separated from an existing from the first material M1 starting sheet. Likewise, the second tooth segments become 23 the teeth 12 cut out of an existing of the second material M2 starting sheet. The connecting part 11 If appropriate, it is separated from a starting sheet consisting of the third material M3. If the second tooth segments 23 and the connecting part 11 consist of the same material, for example, the second material M2, the connecting part 11 together with the second toothed segments 23 the teeth 12 be cut out of the starting sheet in one operation.

The separation from the starting sheet can be done by cutting, punching, laser cutting, water jet cutting or the like.

The first toothed segments are preferred 22 separated by a special separation process from the starting sheet, so as not to adversely affect the magnetic properties at the separation points by heat or material flow when separating out. For example, it is possible to carry out the cutting operation with an advantageous cutting method as shown in FIG EP 1 602 419 A1 is described. The method described therein is incorporated by reference into the application.

Following the separation of the individual components, these are at the joints 25 . 26 connected with each other. As explained, the second connection points 26 between the connecting part 11 and the second toothed segment 23 or the tooth bridge 13 omitted if these two components are made of the same material integrally and separated together from an output sheet.

The connection at the existing connection points 25 respectively. 26 can be cohesive and / or positive and / or non-positive. Preferably, at each junction 25 . 26 a cohesive connection exists, which is optionally supplemented by a positive and / or non-positive connection.

The sheet metal parts of a rotor or a stator are made similar and stacked into a laminated core and connected. This laminated core can then be integrated as usual in the rotor or stator of an electric machine.

The invention relates to a sheet metal part 10 for a stator or a rotor of an electrical machine, for example an electric motor, and a method for producing such a sheet metal part 10 , The sheet metal part 10 has a connecting part 11 on, for example, runs coaxially to a rotation axis D. Transverse from the connecting part 11 protrude regularly spaced teeth 12 path. At the free end, every tooth points 12 a tooth head 14 up, over a tooth bridge 13 with the connecting part 11 connected is. Each tooth has at least a first toothed segment 22 and at least one second toothed segment 23 , The toothed segments are made of different magnetizable materials M1, M2. In this way, the materials M1, M2 can be targeted in terms of their magnetic and / or mechanical properties in the region of the tooth 12 be used where they have the magnetic and / or mechanical behavior of the tooth 12 and therefore the sheet metal part 10 can optimize. In particular, is on the tooth head 14 at least a first toothed segment 22 present, whose saturation magnetization B _{S1 is} greater than that of the rest of the sheet metal part 10 ,

LIST OF REFERENCE NUMBERS

10

 sheet metal part

11

 connecting part

12

 tooth

13

 dental bridge

14

 addendum

15

 free end of the tooth head

16

 Tooth head area

17

 groove

18

 winding

19

 permanent magnet

22

 first toothed segment

23

 second toothed segment

24

 end

25

 first connection point

26

 second connection point

27

 flux conductor

D

 axis of rotation

L

 Longitudinal center plane

M1

 first material

M2

 second material

M3

 third material

R

 direction of rotation

U

 circumferentially

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102012213239 A1 [0006]
• DE 102010049178 A1 [0007]
• EP 1602419 A1 [0036, 0036, 0081]

Claims (17)

Sheet or sintered part ( 10 ) for a stator or a rotor of an electrical machine, with a connecting part ( 11 ), with a plurality of the connecting part ( 11 ) protruding teeth ( 12 ), each at its free end a tooth head ( 14 ), which via a toothed web ( 13 ) with the connecting part ( 11 ), each tooth ( 12 ) at least a first toothed segment ( 22 ) of a magnetizable first material (M1) and at least one second toothed segment ( 23 ) of a magnetizable second material (M2), wherein the magnetizable first material (M1) and the magnetizable second material (M2) are different. Sheet metal or sintered part according to claim 1, characterized in that the magnetizable first material (M1) has a greater saturation magnetization (B _S ) than the magnetizable second material (M2). Sheet metal or sintered part according to claim 1 or 2, characterized in that the magnetizable first material (M1) has a smaller relative permeability (μ _r ) than the magnetizable second material (M2). Sheet or sintered part according to one of the preceding claims, characterized in that the volume fraction of the magnetizable first material (M1) is smaller than the volume fraction of the magnetizable second material (M2). Sheet or sintered part according to one of the preceding claims, characterized in that the first toothed segment ( 22 ) at least a part of the tooth head ( 14 ). Sheet metal or sintered part according to claim 5, characterized in that the tooth head ( 14 ) two first tooth segments ( 22 ) having. Sheet metal or sintered part according to claim 6, characterized in that the two first tooth segments ( 22 ) are arranged in the circumferential direction (U) about the axis of rotation (D) at a distance from each other. Sheet metal or sintered part according to claim 6 or 7, characterized in that the two first tooth segments ( 22 ) symmetrical to a longitudinal center plane (L) through the tooth ( 12 ) are arranged. Sheet metal or sintered part according to one of claims 1 to 6, characterized in that the at least one first toothed segment ( 22 ) asymmetrically to a longitudinal center plane (L) through the tooth ( 12 ) is arranged. Sheet metal or sintered part according to one of the preceding claims, characterized in that the second toothed segment ( 23 ) at least a part of the toothed bridge ( 13 ). Sheet metal or sintered part according to one of the preceding claims, characterized in that the connecting part ( 11 ) and the second toothed segment ( 23 ) consist of the same material (M2). Sheet metal or sintered part according to one of claims 1 to 10, characterized in that the connecting part ( 11 ) consists of a magnetizable third material (M3), wherein the magnetizable third material (M3) differs from both the magnetizable first material (M1) and the magnetizable second material (M2). Sheet metal or sintered part according to claim 12, characterized in that the tensile strength and / or the modulus of elasticity and / or the hardness of the third material (M3) and / or the second material (M2) is greater than the first material (M1). Sheet or sintered part according to one of the preceding claims, characterized in that the first toothed segment ( 22 ) and / or the second toothed segment ( 23 ) positively and / or cohesively and / or non-positively with the respective adjacent part of the sheet metal or sintered part ( 23 respectively. 11 ) are connected. Sheet or sintered part ( 10 ) according to one of the preceding claims, characterized in that the connecting part ( 11 ) is annularly closed in a circumferential direction (U) about an axis of rotation (D) and the plurality of teeth ( 12 ) radially to the axis of rotation (D) of the connecting part ( 11 ) protrude, or that the connecting part ( 11 ) extending in a straight line or curved along a trajectory of the runner and the teeth ( 12 ) obliquely or at right angles from the connecting part ( 11 ) protrude away. Method for producing a sheet metal or sintered part ( 10 ) for a stator or a rotor of an electrical machine, wherein the sheet metal or sintered part ( 10 ) a connecting part ( 11 ) and several from the connecting part ( 11 ) away teeth ( 12 ), which at its free end in each case a tooth tip ( 14 ), which via a toothed web ( 13 ) with the connecting part ( 11 ), comprising the following steps: - producing at least one first toothed segment ( 22 ) for each tooth ( 12 ) of a magnetizable first material (M1), - producing at least one second tooth segment ( 23 ) for each tooth ( 12 ) of a magnetizable second material (M2), wherein the magnetizable first material (M1) and the magnetizable second material (M2) are different, - connecting the at least one first toothed segment ( 22 ) and the at least one second toothed segment ( 23 ) with each other or with at least one further constituent of the sheet metal or sintered part ( 10 ) to the formation of teeth ( 12 ) of the sheet metal or sintered part ( 10 ). Method according to claim 15, characterized in that the second tooth segments ( 23 ) the teeth ( 12 ) before or after connection to the at least one associated first toothed segment ( 22 ) with the connecting part ( 11 ) get connected.

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